Much of the prior two posts would be of only academic interest if tests for legal drugs were job related and consistent with business necessity under § 12113. And, of course, any particular testing regime may well be justified since it’s certainly not implausible that a given employee is unfit for certain tasks while being medicated, and may in fact pose a direct threat to himself or others.

But the question is scarcely a slam-dunk for employers. That's because there's reason to believe that many, perhaps most, people can function well while on medications and subject to doctor supervision. While a testing program can be justified even if it does not perfectly map onto the problem being addressed, there was more than a little concern in the Bates dispute about whether Dura Automotive's program was sufficiently individualized. Arguably, determining the effects of particular drugs might require more focus on the individual case – both the real duties of the position in question and the effects of the medication on the individual employee -- than employers might be inclined to otherwise do.

Further, § 12113(a) requires the employer to show not only the job relation/business necessity but also “that such performance cannot be accomplished by reasonable accommodation, as required by this title.” (The last phrase might limit the accommodation duty to actual disability cases, but we've seen that, post-ADAAA, that is an expanded universe). And § 12113(b), as interpreted by the Supreme Court, permits qualification standards that require that workers not be a "direct threat" to themselves and others.

Thus, the question could be framed either in terms of general qualification standards or, more specifically, in terms of the individual being a direct threat to himself or others. Oddly, the latter may be more difficult for employers than the former. Echazabal read § 12113(b), the direct threat defense, to permit the employer to act when the plaintiff posed a direct threat to himself, but it remanded for an individualized determination in that regard. Other cases have also required employers to document the projected harm to the individual in question. Arguably, a defense that does not rely on the direct threat provision but merely looks to § 12113(a) qualification standard defense might require less individualization, but this is a pretty undeveloped area.

The net result is that, despite Bates, ADA law poses serious challenges for any employer who chooses to test for its employees' use of licit drugs, especially if the employer then acts to exclude such workers without an individualized assessment of their job duties and the effects of such drugs on their capabilities.